Targets

A growth receptor that is mutated in some lung cancers and overproduced in others; the first great success of targeted pills.

A growth-signal receptor. Some cancers make far too much of it, and drugs that block it or use it as a docking site have transformed those cancers.

The signal tumours use to grow their own blood supply. Blocking it starves tumours and, surprisingly, helps immunotherapy work.

CD3 is the switch on every T cell. Bispecific drugs grab it with one arm and the tumour with the other, forcing the T cell to attack.

PD-1 is a brake on T cells. Blocking it releases the immune system against the tumour and has cured some previously incurable cancers.

The hormone switch that drives most breast cancers. Blocking or destroying it is the oldest and most effective targeted therapy.

KIT mutation is the driver behind most gastrointestinal stromal tumours, and the reason imatinib turned a lethal sarcoma into a chronic disease.

KRAS is the most commonly mutated cancer gene, called 'undruggable' for 40 years until 2021.

The hormone switch that drives prostate cancer, attacked by castration and by pills that block the receptor.

PIK3CA is the most commonly mutated gene in hormone-driven breast cancer. Drugs against it work, but hitting it cleanly without raising blood sugar took years.

A gene fusion found in about 5% of lung cancers that responds spectacularly to pills, now for many years.

CD19 is a marker on B cells and B-cell cancers, and was the target of the first CAR-T therapies ever approved.

BCMA is a survival receptor on plasma cells, and the target that made CAR-T and bispecifics work in multiple myeloma.

BRAF is a signalling kinase mutated in half of melanomas; blocking it with two drugs at once became a template for targeted therapy.

FGFR2 is a growth receptor fused in bile-duct cancer and overproduced in gastric cancer.

Somatostatin receptor 2 is a hormone receptor densely present on neuroendocrine tumours, and was the first theranostic target to reach routine care.

The signalling enzyme that B-cell cancers use to survive. Blocking it turned chronic lymphocytic leukaemia into a disease controlled by a daily pill.

CD20 is a B-cell marker; rituximab against it was the first antibody approved for cancer, in 1997.

A receptor that is either mutated in some lung cancers or amplified as an escape route when other lung cancer drugs fail.

A protein on prostate cancer cells that lets doctors both see the cancer on a PET scan and hit it with a radioactive drug.

RET is a kinase altered in thyroid cancer and a small slice of lung cancer, treatable with one selective pill regardless of where the tumour is.

The fusion that defines chronic myeloid leukaemia and a quarter of adult acute lymphoblastic leukaemia; the first cancer driver ever switched off by a pill.

FLT3 is a kinase mutated in about a third of acute myeloid leukaemias, where adding an inhibitor to chemotherapy improves survival.

The signalling enzyme that tells marrow cells to make red cells and platelets; a single mutation (V617F) leaves it switched on in most myeloproliferative neoplasms.

PARP is a DNA repair enzyme. Cancers that have already lost one repair system (BRCA) die when this second one is blocked; healthy cells survive.

PD-L1 is the tumour's side of the PD-1 brake, and also the biomarker that decides who gets immunotherapy.

CDK4/6 is the engine that pushes a cell to copy its DNA. Blocking it alongside hormone therapy roughly doubled the time hormone-driven breast cancer stays controlled.

Folate receptor alpha is a vitamin receptor that ovarian cancer cells carry in large numbers, used as the docking site for the ADC mirvetuximab.

HER3 is a cousin of HER2 that cancers use as an escape route when HER2 or EGFR are blocked.

A metabolic enzyme whose mutant form produces a molecule that scrambles how genes are read; blocking it slows brain tumours and leukaemias.

A gene fusion in about 1-2% of lung cancers that responds for years to targeted pills, now in their third generation.

A protein that sits on the outside of many cancer cells far more than on normal cells, making it a good address for delivering drugs.

AKT is a central survival kinase downstream of PI3K, blocked by capivasertib in breast and now prostate cancer.

DNA repair genes. Inheriting a broken copy raises breast and ovarian cancer risk, but tumours that lose them become uniquely vulnerable to PARP inhibitors and platinum.

A tight-junction protein normally hidden in the stomach lining that becomes exposed in gastric and pancreatic cancers.

The first immune brake ever targeted for cancer; releasing it won a Nobel Prize and cures a fraction of melanomas.

Nectin-4 is an adhesion protein plentiful on bladder cancer cells, used as the docking site for the ADC enfortumab vedotin.

Rare gene fusions found across dozens of cancer types; the first target where a drug was approved for any tumour carrying it.

The switch in the hedgehog developmental pathway that is stuck on in basal cell carcinoma and some medulloblastomas; three approved pills block it.

A protein that stops cells from self-destructing. Venetoclax removes that protection and has transformed leukaemia treatment.

An interleukin receptor over-abundant on a rare aggressive blood cancer and on leukaemia stem cells.

CD22 is a B-cell surface protein and the docking site for the leukaemia ADC inotuzumab ozogamicin.

CD38 is a myeloma surface enzyme and the target of daratumumab, which is now given as a quick under-the-skin injection.

A protein that appears on the surface of small-cell lung cancer cells, now hit by a drug that pulls T cells onto them.

EZH2 is an enzyme that silences genes. The first drug against it treated a rare sarcoma and some lymphomas until it was withdrawn in 2026 for causing second blood cancers.

GD2 is a sugar-fat molecule on the surface of neuroblastoma cells (and some other childhood and adult tumours) with almost none on normal tissue except nerves, which is why anti-GD2 drugs cause pain.

A gene fusion that drives an aggressive leukaemia in infants and adults. It cannot be blocked directly, but the scaffold protein it depends on (menin) can.

LAG-3 is the third immune brake to reach approval, combined with PD-1 blockade in melanoma.

A scaffold protein that certain leukaemias need to keep their genes switched on; the first drug against it was approved in 2024.

TP53 is the 'guardian of the genome', broken in half of all cancers. Fixing it directly has so far defeated every attempt, so drugs exploit what its loss makes cancers depend on.

B7-H3 is an immune-dampening protein on many solid tumours, now used as an ADC address, especially in small-cell lung and prostate cancer.

CCR4 is a chemokine receptor on skin-homing and regulatory T cells, and on the malignant cells of cutaneous T-cell lymphoma and adult T-cell leukaemia; mogamulizumab removes those cells.

CD33 is a myeloid marker and the target of the very first ADC ever approved, in 2000.

The 'don't eat me' signal cancer cells show to macrophages. Blocking it looked promising but the lead drug failed.

CDH6 is an adhesion protein from kidney development that reappears on ovarian and kidney cancers.

The classic 'CEA' tumour marker measured in blood, also present on the cell surface where ADCs can reach it.

The receptor that macrophages depend on; blocking it shrinks tenosynovial giant cell tumour (a CSF1-driven tumour) and depletes tumour-supporting macrophages, though the latter has not yet helped patients with common cancers.

FAP is a protein on the scaffolding cells that surround many tumours, so it lights up almost any solid cancer on a PET scan.

gp100 is a pigment-cell protein, and the target of the first bispecific drug to improve survival in a solid tumour, uveal melanoma.

GPRC5D is a second myeloma target used when BCMA-directed drugs stop working.

A master switch that kidney cancer cells leave permanently on when they lose the VHL gene; belzutifan blocks it.

A relative of PSA that stays attached to prostate cancer cells, used as a T-cell engager address by J&J.

A protein normally only in testis that some sarcomas and other tumours switch on; T cells can be engineered to recognise fragments of it.

NPM1 is the most common mutation in adult leukaemia. It moves a nuclear protein into the cytoplasm and, it turns out, makes the leukaemia dependent on menin.

A protein normally confined to testis that most melanomas and many other cancers switch on; T-cell receptor drugs can recognise fragments of it.

ROR1 is an embryonic receptor re-expressed by many cancers, used as an ADC address in lymphoma and breast cancer.

STEAP1 is a protein on the surface of most prostate cancer cells, now the address for a T-cell engager in phase 3.

TIGIT is an immune brake that looked promising, then failed in several big lung cancer trials. It is a cautionary tale.

Tissue factor is a clotting protein that cancers abnormally display on their surface, used as an ADC target in cervical cancer.

ATR is a DNA-damage alarm kinase. Blocking it makes tumours with broken repair systems collapse under their own replication stress.

CD30 is a protein on the malignant Reed-Sternberg cells of Hodgkin lymphoma and on some T-cell lymphomas, and the address for the ADC brentuximab vedotin.

CD52 is a small protein on nearly all lymphocytes and the target of alemtuzumab, a profoundly immunosuppressive antibody once used in CLL and now mostly in transplant conditioning, T-cell leukaemia and multiple sclerosis.

A T-cell surface marker kept on most T-cell leukaemias; CAR-T cells against it must be engineered not to kill each other, and they have produced remissions in T-ALL where nothing else worked.

CD70 is a protein normally only on activated immune cells, but permanently switched on in kidney cancer and some leukaemias.

CD73 is an enzyme on tumour and immune cells that converts ATP breakdown products into adenosine, a powerful immune-suppressant; blocking it or the adenosine receptors was a major immunotherapy hope that has not yet delivered.

Part of the B-cell receptor found on nearly all B-cell lymphomas; the target of the ADC polatuzumab vedotin and a frequently mutated gene in brain and testicular lymphoma.

A tight-junction protein normally found only in the embryo that reappears in ovarian, testicular, endometrial and lung cancers, making it a clean target for ADCs and CAR-T.

A chemokine receptor that anchors blood cells in the marrow and helps cancer cells home to it; mutated in a third of Waldenström patients and targeted by plerixafor for stem-cell mobilisation.

An adhesion protein on almost all carcinoma cells and the capture molecule for circulating tumour cell tests; the target of the first bispecific antibody ever approved (catumaxomab, 2009).

The fused gene that defines Ewing sarcoma: an aberrant transcription factor that has resisted 30 years of drug design.

Glypican-3 is a fetal liver protein that reappears in liver cancer, giving CAR-T and bispecifics a clean target.

GRPR is a hormone receptor abundant in early and hormone-sensitive prostate cancer, imaged and treated with bombesin-like radioligands.

LIV-1 is an oestrogen-regulated zinc transporter on most breast cancers; the ADC against it (ladiratuzumab vedotin) showed activity in triple-negative disease but was discontinued in 2024.

MDM2 is the protein that degrades p53; blocking it reactivates p53 in tumours where the gene is intact, especially the liposarcomas that carry extra copies of MDM2.

Mesothelin is a surface protein on mesothelioma, ovarian, and pancreatic cancers, targeted by ADCs, CAR-T, and T-cell engagers.

The giant mucin that is shed into blood as the CA-125 ovarian cancer marker; its membrane stalk is being targeted by ADCs and T-cell engagers.

PDGFRA is a growth-factor receptor mutated in about 10% of GISTs, including the D842V mutation that resists imatinib but responds to avapritinib.

An enzyme that cancers lacking the MTAP gene (about 10-15% of all tumours) depend on more than normal cells do; new inhibitors designed to exploit that difference are in late trials.

An immune checkpoint on exhausted T cells and on leukaemic stem cells; antibodies against it failed in lung cancer and MDS after strong preclinical promise.

An immune checkpoint on myeloid cells that works at the acidic pH inside tumours and is a suspected escape route after PD-1 therapy; antibodies are in early trials.

A checkpoint kinase that gives cells time to fix DNA before dividing. Removing it forces damaged cancer cells into a fatal division.

A DNA-unwinding enzyme that mismatch-repair-deficient cancers cannot live without; the first WRN inhibitors are in trials as a chemotherapy-free option for MSI-high tumours that fail immunotherapy.